When to plant in Middlesex, NJ
USDA Zone 7aEverything below — frost dates, hardiness zone, and what to plant when in Middlesex, New Jersey — is derived from the closest NOAA station with complete climate normals.
Zone 7a means many perennials and even some tender shrubs overwinter in Middlesex, while your frost dates still decide when annuals go out.
The average last spring frost in Middlesex is now 5 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
PLAINFIELD · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Middlesex’s own odds, recorded at PLAINFIELD.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 13 | Apr 27 | Apr 12 | Oct 3 | Oct 17 | Nov 1 |
| 32°F | Apr 27 | Apr 11 | Mar 31 | Oct 13 | Oct 28 | Nov 10 |
| 28°F | Apr 11 | Mar 31 | Mar 16 | Oct 24 | Nov 7 | Nov 23 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Middlesex, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 14 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Middlesex planting FAQ
When is the last spring frost in Middlesex, NJ?
Plan for the last spring frost in Middlesex around April 11 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.
When is the first fall frost in Middlesex, NJ?
In Middlesex, the first 32°F freeze of fall lands around October 28 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Middlesex in?
Middlesex is in USDA hardiness zone 7a. In zone 7a, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Middlesex?
There are roughly 200 frost-free days in Middlesex (a moderate growing season), running from the average last frost around April 11 to the first fall frost near October 28.
When should I plant tomatoes in Middlesex?
In Middlesex, start tomato seeds indoors around February 14–February 28, then transplant seedlings outdoors around April 18 once the danger of frost has passed.
Never miss a window in Middlesex
An email when it’s time to start seeds, transplant, and sow — timed to Middlesex’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Bound Brook · 3 km
- South Plainfield · 7 km
- North Plainfield · 7 km
- Martinsville · 7 km
- Somerset · 7 km
- Plainfield · 8 km
- Manville · 9 km
- Somerville · 9 km
Frost dates recorded at PLAINFIELD, 9 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Middlesex, NJ — Frost Dates & Zone 7a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00287079. Retrieved from https://blissgarden.com/new-jersey/middlesex.